DK141684B - PNEUMATIC SUCTION TRANSPORTATION TO SUPPLY MULTIPLE USERS - Google Patents

Description

U168A

The present invention relates to a pneumatic suction conveyor system for supplying multiple users and of the kind specified in the preamble of claim 1.

In a known construction of this structure, the conveyor line opens axially and perpendicularly to the separator's cargo space, see German Publication No. 2,136,328.

The filter is loosely suspended between the outlet of the conveyor line and the separator wall. By establishing a negative pressure in the valve compartment, the filter curves into the clean air space, and the goods arriving via the plug are separated in the fall flow, while the transport air reaches the suction line through the filter. The filter must hereby be dimensioned so that all solid particles are separated from the transport air.

Transport plants of the kind in question are used, for example, in the plastics industry, where several machines are supplied with plastic granules from one or more silos. The said design of the conveyor system is thereby unfortunate because dust particles which occur with the granulate affect the final plastic product mechanically and optically.

The object of the invention is to provide a suction conveying system which ensures the user supply of dust-free material.

This is achieved according to the invention in that the conveyor system is designed as described in claim 1.

This design means that dust is not separated with the transported goods to the user, but passes the separator filter with the transport air. The design also means that the filter resistance in the separators is reduced and that for all users only one common dust separator with high resistance is needed.

Thus, along with the desired functional improvement, a reduction in costs is also achieved.

By the dimensioning according to claim 2, it is achieved that the filter resistance in the separator is not greater than the line resistance. The flow in the filter is thus unobstructed, so that the dust particles are carried safely by the transport air.

2 141686

The invention will now be explained in more detail in connection with the drawing, which schematically shows a plant according to the invention, in which three feed hoppers 1,2,3 corresponding to three storage containers not shown are connected to transport lines 4. Each transport line can be connected to a user's dosing funnel 5 via a separator 6. The conveyed air flow is generated by a fan 7 connected to the separator 6 via suction lines 8,9.

The separators 6 can be connected to any of the transport lines 4 via a branch line 11. This line opens at the bottom of the separator 6 in a cargo space 12. The cargo space 12 is separated from a clean air space 13 connected to the suction line 8,9 by a filter 14 if mesh width is thus chosen that dust particles, but not the supplied goods, can pass. Thus, the supplied goods fall into the cargo space 12, and from this it can be discharged into the hopper 5. Particles, including dust, of smaller particle size than that which is desired to be retained in the filter 14, are thus carried by the conveying air to the suction line 8,9.

Therefore, in front of the suction nozzle 15 of the blower 7, a filter 16 is provided with a plurality of fine-mesh filter bags 17 which retain the dust particles content of the transport air.

Thus, this filter is common to all users and exhibits relatively high flow resistance, while the filters 14 in each user's separator are preferably selected with a flow cross-section greater than the flow cross-section of suction line 8.9.